I'm walking the French Way in May, 2013 and downloaded the Kindle App on my iphone 5 from which I purchased the the book
CAMINO DE SANTIAGO History Culture Architecture from St. Jean Pied De Port to Santiago De Compostella and Finesterre by Gerald Kelly, updated summer, 2012.
It is the best, most efficient guide book I have found and I don't have to worry about the weight of a paper guide book since it is on my iphone. Since it is a Kindle book, I can increase the font size and won't have to use my reading glasses and can view it night or day with the lit screen.
The guide not only has maps and directions of main and alternative routes and maps of the cities, but also history along the Camino and historical sites to visit, places to stay, eat, and shop, and other valuable information. I believe the author also has the same offerings in books on other routes than the French Way.
The best map I found is the Google Map. You can choose your route and view it as a flat map or satellite view:
http://www.elcaminosantiago.com/Camino-Santiago-Maps.htm and see great detail by zooming in on the screen down to terrain, city streets and houses, and highlights in yellow the route you choose to take.
See the google map website for the French Way here:
http://www.elcaminosantiago.com/Camino-Santiago-Map-Camino-Frances-Google.htm
Along with the app for this forum to help me find all of the albergues on the trail, the Kindle guide book and the Google map will definitely help me stay on the right path, offer alternatives, and let me find what I need on the way.
I hope this will help someone.